The problems caused by the accumulation of static electricity on insulating materials and especially on textiles containing synthetic fibers comprised of polymers with hydrophobic groups and other low conductive materials are well-known. These problems include:
STRONG, DISAGREEABLE SHOCKS CAUSED BY THE RAPID DISCHARGE OF ACCUMULATED STATIC ELECTRICITY;
ATTRACTION OF DUST FROM THE ATMOSPHERE TO THE FABRIC TO FORM SOILED SPOTS THEREON; AND
DETRIMENT TO THE FUNCTIONING OF SENSITIVE ELECTRONIC EQUIPMENT BECAUSE OF STATIC-ELECTRICITY DISCHARGES.
Furthermore the problems posed by the accumulation of static electricity have taken on new meaning in view of recent changes in modern living. More and more synthetic textiles are used in the home and the increase in the use of central heating throughout the world helps to create a dry atmosphere which aids in the accumulation of static charge. The three ways known heretofore to combat the problem of static electricity in synthetic fibers are as follows:
USE OF HIGHLY CONDUCTIVE THREADS OR FIBERS AS THE TEXTILE MATERIAL;
INCORPORATION INTO THE FABRIC OF VERY FINE STEEL WIRES; AND
APPLICATION OF CHEMICAL ANTISTATIC AGENTS TO COAT THE FIBERS.
None of the above methods has been truly successful.
It is the last of the three methods mentioned above which is most currently used wherein the conductive additives (e.g. nitrogen-containing polymers, surface-active oxyethylenes, phosphoric acid esters) are introduced into the fiber or filament binding compositions by spraying onto the surface of the substrate textile material.
In Ser. No. 601,042 filed Aug. 1, 1975 (now U.S. Pat. No. 4,053,440), new latex compositions sensitive to heat are disclosed. These latex compositions contain a thermosensitizing agent comprising a urethane-alkylene copolymer of the formula: EQU (O.dbd.C.dbd.N).sub.x --R--[--NH--CO--O--C.sub.n H.sub.2n --O).sub.p --R'].sub.y
wherein R is an aliphatic or aromatic moiety which contains biuret groups, urethane groups, or isocyanate groups; R' is selected from the group which consists of hydrogen, C.sub.1 to C.sub.1 alkyl having a straight or branched chain, aryl and alkylaryl, x is 0 to 1, y is always greater than 2, n has a value of 1 to 4 inclusive and p has a value of at least 5. These polymers are described as having the ability to lower the coagulation temperature of latex polymers.